This invention relates generally to improvements in cleaning devices and equipment for use in cleaning swimming pools and the like. More particularly, this invention relates to an improved filter bag for use with a swimming pool cleaner of the type designed for travel over submerged pool surfaces to collect grit and debris settled thereon, wherein the improved filter bag is designed for facilitated assembly and subsequent quick release mounting onto a pool cleaner in a manner to insure proper and pre-aligned orientation of the filter bag on the pool cleaner.
Automatic swimming pool cleaners are generally well known in the art for use in maintaining a swimming pool in an overall state of cleanliness. In this regard, residential and commercial swimming pools normally include a standard water filtration system including a main circulation pump and related main filter unit for filtering the pool water. The filtration system is typically operated for several hours on a daily basis to draw water from the pool for flow through the main filter unit and subsequent return circulation to the pool, wherein the filter unit includes an appropriate filter media for collecting and thus removing solid debris such as fine grit and silt, twigs, leaves, insects, and other particulate matter suspended within the pool water. Although such filtration systems function efficiently to collect suspended particulate, it has been recognized that some particulate tends to settle onto submerged pool floor and wall surfaces and thus is not removed by the standard filtration system. Automatic swimming pool cleaners have been developed and are widely used to assist in a more thorough cleaning of the pool by directly collecting such settled matter, and/or by re-suspending the settled matter so that it can be collected by the main filter unit.
More specifically, in one common form, the automatic swimming pool cleaner comprises a relatively compact wheeled housing adapted to travel randomly over submerged floor and wall surfaces of the pool. The cleaner is normally connected by a hose into the standard filtration system, such as by connection to the positive pressure discharge side of the system as described in U.S. Pat. Nos. 4,558,479; 4,589,986; and 3,822,754, or by connection to the negative pressure suction side of the system as described in U.S. Pat. Nos. 5,105,496; 4,729,406; and 4,643,217. In either case, the filtration system provides a water flow to and through the cleaner, wherein this water flow is typically used to create or induce a suction flow through a suction mast for vacuuming grit and debris through the suction mast into a porous mesh filter bag mounted on a downstream end thereof. The water flow through the pool cleaner is also frequently used to power a hydraulic drive means which causes the cleaner to travel about within the swimming pool. The filter bag is designed for periodic removal from the cleaner so that accumulated debris therein can be disposed, followed by re-mounting of the filter bag onto the pool cleaner.
Filter bags for pool cleaners are commonly constructed and shaped for mounting onto the pool cleaner in a predetermined orientation in order to achieve maximum cleaning effectiveness. In particular, according to one common filter bag configuration, the bag is designed with an open mouth connected to a mounting collar or the like adapted for removable mounting onto an upper end of the suction mast. The bag is shaped to define an interior which extends upwardly above the mouth and then expands rearwardly. With this geometry, debris flowing upwardly from the suction mast into the bag interior will tend to displace to and settle within a rear region or pocket of the bag as a result of the forward motion of the pool cleaner. Debris retention within the rear pocket is important to prevent collected debris from falling back through the suction mast when the pool cleaner, normally operated on an intermittent basis, is turned off. Some filter bags include a releasable seam at the rear pocket for facilitated emptying of the bag. Exemplary filter bags of this general type are shown and described in U.S. Pat. Nos. 4,618,420; 4,575,423; and 288,373.
In the past, filter bags for pool cleaners have been susceptible to mounting of the bag onto the pool cleaner suction mast in an incorrect orientation, typically by permitting the bag to be installed backwards with the rear pocket extending forwardly from the suction mast. Improper bag orientation can also occur as a result of incorrect assembly of the bag with the related mounting collar during filter bag manufacture. Such incorrect bag mounting results in inefficient pool cleaner operation and creates the potential for dissatisfaction among pool cleaner customers.
There exists, therefore, a significant need for improvements in and to filter bags for pool cleaners, wherein the filter bag is designed for correct, unidirectional or one-way mounting onto the suction mast of a pool cleaner. The present invention fulfills this need and provides further related advantages.